21452549 has 2 divisors, whose sum is σ = 21452550. Its totient is φ = 21452548.

The previous prime is 21452533. The next prime is 21452567. The reversal of 21452549 is 94525412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11730625 + 9721924 = 3425^2 + 3118^2 .

It is a cyclic number.

It is not a de Polignac number, because 21452549 - 2⁴ = 21452533 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is a plaindrome in base 11.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21452569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10726274 + 10726275.

It is an arithmetic number, because the mean of its divisors is an integer number (10726275).

Almost surely, 2^21452549 is an apocalyptic number.

It is an amenable number.

21452549 is a deficient number, since it is larger than the sum of its proper divisors (1).

21452549 is an equidigital number, since it uses as much as digits as its factorization.

21452549 is an evil number, because the sum of its binary digits is even.

The product of its digits is 14400, while the sum is 32.

The square root of 21452549 is about 4631.6896484976. The cubic root of 21452549 is about 277.8601724228.

The spelling of 21452549 in words is "twenty-one million, four hundred fifty-two thousand, five hundred forty-nine".